A controller area network (CAN) is a computer network serving measurement and control instrumentation intercommunication in technical fields, more particularly in motor vehicles and in measurement and control technology. The CAN bus is a two-wire bus. Whilst motor vehicles usually always contain the same measurement and control instrumentation, the addresses of which are dedicated, in measurement and control technology the number of bus subscribers allocated addresses in each case varies and is initially unknown.
Hitherto CAN bus subscriber addresses were set by means of hardware switches by the user, this harboring the risk of the same address being allocated multiply due to a wrong setting. In addition to this the setting needs to be made before other configurations can be implemented which causes additional trouble to the user. Furthermore, address allocation is an activity, the use of which is not immediately apparent to the user since it is lastly of no concern to him how the individual bus subscribers swap information.
Described in EP 0 221 303 B1 is a method of automatically allocating addresses in a computer network. However, this known method requires a bus having more than two wires as well as the existence of a host processor, it thus not being suitable for a CAN environment, i.e. in a network in which only one two-wire bus is available and all bus subscribers have substantially the same priority.